If I select a single vertex and drag, the whole object stretches out instead of just the vertex selected
You can subdivide and It'll add another geometry and then when u select the object from the subdivision you can drag it and it'll stretch out from the subdivision only.
You can add subdivision by pressing &quot;R&quot; and you can scroll up or down in order to increase the no. of subdivision.And then right click if u want it to stay on center.
Thank you hope it'll help